GEORGE FREDERICK BARKER. xv 



regard by those who knew him, and his death brought to them a 

 deep sense of irreparable personal loss. His earnest interest in 

 science is attested by the numerous papers which form a partial 

 record of his thought and work, while his fine personal traits remain 

 to those who new him as a memory which will not soon fade. 



In the early Philadelphia days Dr. Barker lectured frequently 

 in public to large and appreciative audiences. He spared no pains 

 to interest and instruct those who attended. Was there a new 

 development or discovery in science, he strove to make his auditors 

 appreciate it as he did. His mechanical and practical skill was of 

 great aid in devising and arranging apt and often brilliant experi- 

 mental illustrations, with which his popular lectures were crowded. 

 It was the writer's privilege as a young man to be present on a 

 number of such occasions at the Academy of Music, and he remem- 

 bers vividly a lecture on electric lighting in which, as a unique 

 feature, an early Gramme dynamo, secured from abroad by Dr. 

 Barker, was driven by a gas engine, and used to furnish the elec- 

 trical current. Before that time a large voltaic battery, almost pro- 

 hibitive from its cumbersomeness and cost, would have been required 

 to produce any semblance of the brilliant efifects of the electric arc 

 then shown. This was at a time when there was but little appre- 

 ciation of the possible great future growth of electric lighting, and 

 about two years before the invention of the incandescent lamp by 

 Edison. 



As a natural result, however, we find that Dr. Barker was not 

 only, from the first, in personal touch with Edison in his pioneer work, 

 but was one of those deeply interested in his early incandescent lamp 

 development. More broadly it can be said that throughout his long 

 service to science, Dr. Barker followed with special ardor the rapid 

 and important growth of electrical science which has continued in 

 the intervening years. 



When the American Philosophical Society celebrated the 150th 

 anniversary of its foundation, it was he who, under the title of 

 "Electrical Progress Since 1743." studiously reviewed the advance 

 of electrical science due to workers such as Franklin, Faraday, 

 Hare, Henry and others. As another evidence not only of his deep 



